HD 4K 10-300X40mm Super Zoom Monocular Telescope BAK4 Prism for Hiking
Prism: BAK4 prism. Type: Monocular. Used for: racing, beach, bird watching, boating/yachting, horse racing, hunting, outdoor activities, sports, theater, travel. Step 3: Slightly extend the stretch ring outward by about 1 cm to see clearly.